It is a busy month for them, with son Leo’s second birthday, wife Anna’s birthday, and an anniversary.

Playing in the back of their minds, always, is the thought that this could be their last birthday, anniversary, or Christmas together.

In September 2014, Pat Dennis was diagnosed with Hemophagocytic Lymphohistiocytosis, or HLH, a rare and potentially fatal immunodeficiency.

He was the first person in Tasmania to be diagnosed with the disease.

There has been one since, who passed away six months after being diagnosed. There is no indication of how long Pat has before, or if, the disease claims his life, too.

The journey to the diagnosis was a long one; Pat was first diagnosed and treated for epilepsy.

A chance trip to the hospital’s emergency room with a suspected allergic reaction to a new drug saved Pat’s life – doctors discovered his liver was shutting down, and he was admitted.

He would go on to spend considerable time in ICU, and was put on life support and in an induced coma.

The first he knew of his illness was waking up and reading a “chemotherapy restrictions” poster on his hospital room door.

He woke up to a new world: he had lost half his body weight, could not move his legs or left arm, and he had a name for the condition that had been plaguing him.

All the while, Anna was seven months pregnant with their first child.

“The whole way through we didn’t know if he would be alive or able to be at the birth,” Anna said.

As the birth drew closing, Pat was struck down with a viral infection and moved to another ward, which was subsequently shutdown amid a gastro outbreak.

Anna would hold up newborn Leo in a corridor that ran adjacent to the isolation rooms so that Pat could peer through the windows to see his son.

“That was into the new year. We really didn’t have a lot of contact at that time,” Anna said.

The prescribed treatment for HLH is chemotherapy, and a bone marrow transplant.

For the present, Pat takes an experimental drug that was brought in the from the United Kingdom.

It is not curing him, but it is maintaining him.

“The plan (from the outset) was to keep me alive long enough to do the bone marrow transplant,” Pat said.

“The only long-term solution for HLH is either the drug that I am on, or a bone marrow transplant.

“We spent about one year focusing on going to Melbourne (for the transplant). I was learning to walk again, and putting on weight. But Melbourne pulled the pin and said there couldn’t be an outcome better than we have.

“From then the focus switched to quality of life and spending as much quality time with Leo as I can, and creating a legacy for him.”

Pat was 15 when his father passed away.

His dad, a builder, had amassed a lifetime of tools. Unwittingly, his mother gave them away after his death.

Pat wants to pass down a lifetime of tools to Leo, an aim that he has turned to Go Fund Me to help achieve.

“If it were up to me, I’d teach him myself, in the shed. But it’s likely that’s not going to happen,” he said.

“But it’s giving him the option of having an idea in the back of his mind and having the tools and the support structure to make that happen.”

“For me, it’s about getting HLH out there. Pat just wants to be able to create more memories for Leo.” Anna said.

High school sweethearts who have been together for 20 years, Pat and Anna are originally from Darwin, and moved to Tasmania in 2011, buying up a little farm at Elizabeth Town.

Pat picked up a metal fabrication apprenticeship.

They now call Longford home, and have been humbled by the support offered by the community.

“It’s weird to say but this sickness has made us a lot of friends.We didn’t have a lot of close support but people were amazing. I’d come home and my lawn would be mowed, and I’d have no idea who it was,” Anna said.

“Pat’s work refused to stop paying him from September to February (even though he was not working and it was likely that he would not come back) simply because they wanted to help us.”

“A friend of mine, who is just a young fella, got two weeks off work and stayed with Anna and Leo when they first got home,” Pat said.

“The poor guy had never touched a baby in his life. Suddenly he was doing nappy runs to the supermarket for us,” Anna added.

The support continues. Mates have fundraised to buy Leo a cubby for his birthday, and others have pulled together cash for the festive season.

“This will be the first Christmas that we’ve had at home since it all started. We’re going all out,” Anna said, as Pat yelled out “prawns!”.

“Some friends have raised some money so that we have an indulgent birthday and Christmas so that we don’t have to think about the realities of life.”

Now is the critical time in Pat’s HLH journey. According to research, many people incur severe relapses at the two to two-and-a-half year mark.

A common cold could kill him, and he has to go to the emergency department every few months. “We think, ‘Is this it?’,” Anna said of the visits.

Soon, the possibility of a bone marrow transplant gets put back on the table. A donor has been lined up almost since the start.

Their situation is unimaginable, but the pair confess that they cope pretty well “most of the time”.

“As for the future, we’re just going to keep truckin’,” Pat said.

HLH, or Hemophagocytic Lymphohistiocytosis, is a life-threatening immunodeficiency. It is more common in children. It is not a form of cancer but is treated similarly to leukemia. The life expectancy is five years.